Lifting jack



J. J. MIZER LIFTING JACK Filed Dec. 17, 1925 2 Sheets-Sheet l Sept. 30 1924. 1,510,011

J. J. MIZER LIFTING JACK Filed Dec. 17 1923 2 Sheets-Sheet. 2

Patented Sept. 30, 1924.

UNITED STATES PATENT OFFICE.

JOSEPH J'. MIZER, OF RACINE, WISCONSIN, ASSIGNOR TO WALKER MANUFACTURING COMPANY, OF RACINE, WISCONSIN, A CORPORATION OF WISCONSIN.

LIFTING JACK.

Application filed December 17, 1923. Serial No. 681,196.

To all whom it may concern:

Be it known that I, JOSEPH J. MIZER, a citizen of the United States, residing at Racine, in the county of Racine and State of Wisconsin, have invented certain new and useful Improvements in Lifting Jacks, of which the following is a specification.

My invention relates to lifting jacks of the type in which a vertically disposed lifting bar having a load supporting member upon its upper end is slidably mounted with respect to a suitable standard, and it is the principal object of my invention to provide a new and improved form and arrangement of parts for holding the lifting bar slidably in position, whereby the friction between the parts and the wear in service may be reduced to a minimum.

It is another object of my invention to provide new and improved means for slid ably mounting in position on one face of the jack a vertical bar upon which an auxiliary load supporting member may be adjustably mounted.

'The preferred means by which I have accomplished my several objects are illustrated in the several drawings and are hereinafter specifically described. That which I believe to be new and desire to cover by Letters Patent is set forth in the claims.

In the drawings:

Fig. 1 is a side view of my improved jack.

Fig. 2 is a vertical section taken at line 22 of Fig. 1.

Fig. 3 is an enlarged detail view, partly in section, showing the construction of the operating parts.

Fig. 4: is a horizontai section taken at line 44 of Fig. 1.

b Fig. 5 is a perspective view of the lifting Fig. 6 is a side view of a modified form of construction.

Fig. 7 is a horizontal sectional view taken at line 77 of Fig. 6.

Fig. 8 is a side view of a second modified form of construction.

Fig. 9 is a horizontal section taken at line 99 of Fig. 8.

In jacks of this general type, in use heretofore, it has been customary to provide a standard in the form of a channel with a lifting bar slidably mounted between the flanges of the channel, a keeper being the operatin mounted between the flanges extending across the face of the lifting bar for holding the bar in operative adjustable position.

In order that the upward movement of the lifting bar should not be unduly limited, the keeper has, of course, been placed at or near the upper end of the standard and in this position has had a limiting effect upon mechanism of the jack. By my improve arrangement, in which the retaining means for the lifting bar is in the form of elongated tongues and grooves engaging between the front and rear faces of the lifting bar, the lifting bar has been provided with adequate bearings for holding it in proper alignment without undue wear upon the parts, and any tendency to restrict the action of the operating levers and pawls has been entirely avoided.

In my improved construction (see Figs. 1 to 5), 15 indicates a base of any approved type, being preferably in the form as best shown in Fig. 2, comprising a plate of sheet metal pressed into form with a central depression 16 extending longitudinally thereof. A standard 17, preferably formed of sheet metal is secured in position upon the base 13 by means of outwardly extending flanges 18, reinforcing ribs 19 being preferably provided for bracing the flanges 18 with respect to the standard 17.

- As is best shown in Fig. 4, the standard 1.7 is in the form of a channel, the flanges of the channel being provided with longitudinally extending ribs 20 upon their inner faces, such ribs being produced by pressing grooves 21 in the outer faces of the flanges. This construction provides in effect grooves 22 in the inner faces of the flanges of the channel member adjacent to the Web portion of the channel. This construction also provides in effect ribs 23 on the outer faces of the flanges adjacent to the web portion of the channel.

The lifting bar of my improved jack comprises a bar 24 preferably in the form of a casting, having rack teeth 25 upon its for- Ward face. The bar 24 is provided with grooves 26 in its side faces, this construction in effect providing ribs 27 upon its side faces adjacent to the rear face of the bar. As is clearly shown in Fig. 4c, the lifting bar is mounted within the channel 17 between the flanges thcreof in close proximity to the web of the channel, the ribs 20 being in sliding engagement withthe grooves 26, and the ribs 27 of the bar being in engagement with the grooves 22 in the inner faces of the flanges of the channel member. The bar 24 is provided at its upper end with a load support 28 of any suitable type. A lug 29 carried by the bar 24 serves to limit the upward movement of the bar with respect to thestandard 17 by engagement with a tongue 30 pressed inwardly from the metal of one of" the flanges of the channel, as is clearly shown in Figs. 1 and 2.

As is shown in Fig. 3, the operating mechanism for controlling the movement of the lifting bar 24 comprises a lever in the form of. a bar 31 secured in a socket member 32 pivotally mounted upon a pin 33 extending between the .flanges of the channel member 17. The lever is provided with two pawls 34 and 35 pivotally mounted with respect to the lever, in position for en aging the teeth 25 of the lifting bar 24. 'ontrolling means for the pawls 34 and 35 is provided comprising a cam member 36 pivotally mounted upon the pin 33, such cam member being adapted to engage lugs 37 and 38 upon the pawls .34 and 35, respectively, for controlling the operation of the pawls in the well understood manner. A spring 39 of any approved type is connected with the cam member 36 for holding such member yieldingly in either of two operative positions, depending upon whether the stroke of the lever is to be a raising stroke or a lowering stroke, the spring 39 being supported, in'the construction shown, by a plate 40 of any approved type, secured between the flanges of the standard. Inasmuch as the operating mechanism forms of itself no part of my present invention, it is believed that it will not be necessary further to describe the construction and operation of the parts.

As will be readily understood, by the use of the elongated tongue and groove connection engaging between the front and rear faces of the lifting bar, such retaining parts have no tendency whatever to limit the builder in the matter of the design of the operating parts by which the bar is raised and lowered. By reason of the fact that the bearings extend substantially the full length of the bar and the standard, the danger that the bar will become cramped and held against free movement with respect to the standard, is eliminated. Moreover, by the provision of the bearings of very considerable length, the wear upon the parts is distributed and rapid wear at any one point is prevented.

In Figs. 6 and 7 corresponding parts are indicated by the same reference characters.

In this construction, a second bar 41 is connected at its upper end with the bar 24, such bar 41 being located in parallelism with the lifting bar 24 but along the outer face of the channel member comprising the standard member 17. At its lower end the bar 41 is provided with a clip 42, the end portions of which are bent inwardly to embrace the ribs 23 upon the outer faces of the flanges of the channel member 17. The clip 42 thus serves to hold the bar 41 slidably in suitable position with respect to the bar 24 which is likewise guided by the same rib and groove construction.

As is best shown in Fig. 7, in the construction shown the bar 41 is in the form of a channel having teeth 43 formed upon the rear edges of the flanges for holding in adjusted position a load support 44 which is slidably mounted upon the bar 41, being held in position with respect thereto by means of a short arm 45 adapted to engage the teeth of the bar 41.

The construction shown in Figs. 8 and 9 is similar to that shown in Figs. 6 and 7, except as to certain of the details of construction. In the device of Figs. 8 and 9, a load support 46 is mounted upon the upper end of the lifting bar 24, being of different form from that shown in Fig. 1, in that such support comprises a downwardly turned arm 47 to which the upper end of a bar 48 is connected, such bar 48 corresponding to the bar 41 of Fig. 6. The bar 48 is also in the form of a channel, but with the edges of the flanges turned inwardly, the teeth 49 of the bar 48 being pressed inwardly from the web of the channel member in lieu of the form of teeth shown in Fig. 6. The load support 50 adjustably mounted upon the bar 48 is slidably mounted upon the bar 48 by means of a head 51, the engagement with the teeth 49 being efi'ected by a detent 52. The lower end of the bar 48 is slidably connected with the standard 17 by means of a clip 53 corresponding in construction and operation to the clip 42 ofthe construction of Fig. 6.

While I prefer to employ the forms of construction as illustrated in the several figures of the drawin s, it will be understood that I do not wish to be restricted to the particular form of parts as there shown except as such detailed construction may be hereinafter specifically claimed, inasmuch as it is evident that various changes might be made in the particular form of construction without departing from the spirit of my invention.

I claim:

1. A jack comprising a standard in the form of a channel member comprising a continuous web and substantially parallel side flanges, there being inwardly extending ribs pressed from each flange extending parallel to the Web, thus forming interior grooves or channels adjacent the web, and exterior grooves parallel with the Web and interior grooves, a lifting member comprising a pair of bars connected at their upper ends, one sliding inside the channel and guided by the inner grooves, and the other mounted outside the web and having extensions at its lower end engaging in and guided by the exterior grooves.

2. A jack comprising a standard in the form of a channel member comprising a continuous web and substantially parallel side flanges, there being inwardly extending ribs pressed from each flange extending parallel to the web, thus forming interior grooves or channels adjacent the web, and exterior grooves parallel with the web and interior grooves, a lifting member comprising a pan of bars connected at their upper ends, one sliding inside the channel and guided by the inner grooves, and the other mounted outside the web and having extensions at its lower end engaging in and guided by the exterior grooves, lifting means mounted between the flanges and engaging the inner bar, and a load support adjustably mounted on the outer bar.

JOSEPH J. MIZER. 

